Rotary cutter assembly for road milling machines

ABSTRACT

A sealing assembly for a rotary cutter assembly is provided. The rotary cutter assembly includes a rotary cutter tool, a driver shaft, a housing, a side plate, and the sealing assembly. A neck portion of the driver shaft extends outwards of a first cutout section of the side plate. The sealing assembly is arranged about the first cutout section. The sealing assembly includes a guard member. The guard member is slideably arranged relative to the side plate. In a retracted state of the side plate, the guard member is positioned adjacent to and proximal to a lower portion of the side plate. In an extended state of the side plate, a second cutout section of the guard member engages with the neck portion and limits a movement of the guard member, to position the guard member distal to the lower portion of the side plate.

TECHNICAL FIELD

The present disclosure generally relates to a rotary cutter assembly for road-milling machines. More particularly, the present disclosure relates to a sealing assembly employed with a side plate of the rotary cutter assembly.

BACKGROUND

Road-milling machines, also known as pavement profilers, cold planers or road planers, are machines designed for scarifying, removing, mixing or reclaiming material from roadway and similar surfaces. These machines typically have a rotary cutter assembly, to perform milling operations. The rotary cutter assembly includes a rotary cutter tool that is vertically adjustable with respect to a working surface. Rotary cutter tools are generally enclosed within a housing that prevents the uncontrolled discharge of a cut roadway material from the housing. During operations, therefore, the rotary cutter tool is enclosed within the housing and at the same time is removing material to a predetermined depth below the working surface. For this purpose, the housing and the rotary cutter tool are elevationally adjustable with respect to ground.

The rotary cutter tool is generally mounted on an externally driven rotatable shaft or a driver shaft, which may have a portion extending beyond the housing. Therefore, a clearance or a cutout section for the driver shaft is provided in the housing. Also, side plates are provided around the housing that contain a material discharge within the housing, during operations. These side plates also include a cutout section complying with the cutout section of the housing, and which provide a clearance for the driver shaft to be extended outwards. More particularly, the cutout section in the side plate permit a vertical movement of the rotary cutter tool and the housing, into a working area devotionally lower than a surrounding roadway surface. As the side plates are lowered and raised relative to the rotary cutter tool, situations arise where the cutout section in the side plates define a relatively large gap between the driver shaft and the side plates, allowing an amount of milled material to be unduly discharged from the housing.

Conventional arrangements to counter such situations includes the use of flexible mats and skirts that are positioned across the cutout section. Such mats and skirts generally facilitate deflection of the discharge, as a position of the housing is adjusted relative to the rotary cutter tool and the gap becomes bigger. However, such provisions, typically constructed of heavy canvas or rubberized materials, are only partially effective in retaining the cut material within the housing. This is true particularly when the mats or skirts are punctured when subjected to hurled, relatively heavy pieces of broken paving material. Moreover, such mats and skirts are prone to wear and tear, thus requiring frequent repairs or replacement.

U.S. Pat. No. 4,938,537 discloses an end closure for a housing on a road planer, and more particularly to a self-actuating end closure for the housing. Although the '537 discusses provisions for restraining the undue discharge of paving materials out of the housing, an arcuate shape imparted to the of the edges of the end closure results in a portion under the end closure to remain substantially uncovered. A postulation for the need of an additional plate to this portion may cause limitations to the movement of the driver shaft. Therefore, scope for improvement remains to further contain the discharge of paving materials that may escape without an actual increase in the bulk of the end closure. Moreover, room remains for such provisions to possess a further simplified overall structure.

Accordingly, the system and method of the present disclosure solves one or more problems set forth above and other problems in the art.

SUMMARY OF THE INVENTION

Various aspects of the present disclosure describe a road-milling machine. The road-milling machine includes a rotary cutter assembly. The rotary cutter assembly includes a rotary cutter tool, a driver shaft, a housing, a side plate, and a sealing assembly. The rotary cutter tool has a drive axis. The driver shaft is coaxially attached to the rotary cutter tool along the drive axis. The driver shaft is adapted to rotate the rotary cutter tool. The driver shaft includes a neck portion. The housing defines a first side and a second side. The housing is adapted to house the rotary cutter tool and at least a portion of the driver shaft. The side plate is installed on the first side of the housing. The side plate has a first cutout section. The first cutout section defines a clearance space that allows the neck portion of the driver shaft to extend outward of the side plate. Moreover, the side plate is movable between an extended state and a retracted state relative to the neck portion of the driver shaft. The sealing assembly is installed proximal to the first cutout section of the side plate. The sealing assembly includes a guard member. The guard member is slideably arranged relative to the side plate. The guard member includes a second cutout section that allows the driver shaft to extend outward of the sealing assembly. In the retracted state of the side plate, the guard member is positioned adjacent to and proximal to a lower portion of the side plate. In the extended state of the side plate, the second cutout section of the guard member engages with the neck portion and limits a movement of the guard member, to position the guard member distal to the lower portion of the side plate.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a rear pictorial view of an exemplary road-milling machine installed with a rotary cutter assembly, in accordance with the concepts of the present disclosure;

FIG. 2 is a side view of the rotary cutter assembly of the road-milling machine of FIG. 1, with a side plate depicted in a retracted state, and with an exemplary sealing assembly installed, in accordance with the concepts of the present disclosure;

FIG. 3 is a side view of the rotary cutter assembly of the road-milling machine of FIG. 1, with the side plate depicted in an extended state, and with the sealing assembly installed, in accordance with the concepts of the present disclosure;

FIG. 4 is a front exploded view of the sealing assembly of FIGS. 2 and 3, in accordance with the concepts of the present disclosure; and

FIG. 5 is a rear exploded view of the sealing assembly of FIGS. 2 and 3, in accordance with the concepts of the present disclosure.

DETAILED DESCRIPTION

Referring to FIG. 1, there is shown a rear pictorial view of a road-milling machine 10. The road-milling machine 10 is a cold planer that perform milling operations on a work surface 12, such as but not limited to, paved area laid over a road, paved area laid over a bridge, or paved area laid over a parking area. The road-milling machine 10 includes a main frame 14, a number of drive units 16, a conveyor unit 18, and a rotary cutter assembly 20. Although the cold planer is shown as a preferred embodiment of the road-milling machine 10 in the present disclosure, it may be noted that the road-milling machine 10 may embody any construction machinery that includes the rotary cutter assembly 20. For example, concepts of the present disclosure may also be applied to a rotary mixer machine.

The rotary cutter assembly 20 performs milling operations on the work surface 12. The rotary cutter assembly 20 is structurally supported on the main frame 14, which in turn, is supported on the drive units 16. The drive units 16 facilitate the road-milling machine 10 to travel along a length of the work surface 12 and therefore facilitate the rotary cutter assembly 20 to perform milling operation on the entire length of the work surface 12. Moreover, the rotary cutter assembly 20 is positioned proximal to the conveyor unit 18, such that the milled off material is transferred to a nearby positioned truck (not shown), via the conveyor unit 18.

Referring to FIGS. 2 and 3, there is shown the rotary cutter assembly 20. The rotary cutter assembly 20 includes a rotary cutter tool 22 (FIG. 2), a driver shaft 24 (towards left hand side of the road-milling machine 10), a stub shaft (towards right hand side of the road-milling machine 10), a housing 26, a frontal door 28, a rear door 30, two side plates 32 (one towards left hand side and one towards right hand side of the road-milling machine 10), and a sealing assembly 34. Although, structure and arrangement of the driver shaft 24 and a singular side plate 32, installed on a first side 36 of the housing 26, will be described hereinafter, similar structure and arrangement of the stub shaft (not shown) and the other side plate 32, installed on a second side 38 of the housing 26, may also be contemplated.

The rotary cutter tool 22 (FIG. 2) is a cylindrical structure that supports a number of tangentially positioned cutting tools, along its periphery. The rotary cutter tool 22 (FIG. 2) includes a drive axis (not shown). To facilitate the milling operation, the rotary cutter tool 22 (FIG. 2) is rotated over the work surface 12 and along the drive axis (not shown), which causes at least a portion of the work surface 12 to be broken and removed off from the work surface 12. Further, the rotary cutter tool 22 (FIG. 2) is driven by the driver shaft 24.

The driver shaft 24 is coaxially attached to the rotary cutter tool 22 (FIG. 2), along the drive axis (not shown). The driver shaft 24 rotatably supports the rotary cutter tool 22 (FIG. 2) on the main frame 14 and is adapted to rotate the rotary cutter tool 22 (FIG. 2). More specifically, the driver shaft 24 attaches to the rotary cutter tool 22 (FIG. 2) and extends outwards of the housing 26, to connect to a drive motor (not shown). The drive motor (not shown) rotates the rotary cutter tool 22 (FIG. 2), via the driver shaft 24, to perform milling operation on the work surface 12. The driver shaft 24 defines a neck portion 40 that extends outward of the housing 26 of the rotary cutter assembly 20.

The housing 26 is a cover unit that encloses the rotary cutter tool 22 (FIG. 2) and a portion of the driver shaft 24 of the rotary cutter assembly 20. The housing 26, in conjunction with the frontal door 28, the rear door 30, and the side plate 32, prevents unwanted discharge of the milled material from the rotary cutter assembly 20. In general, a lower portion 42 of the side plate 32 abuts against the work surface 12, while the rotary cutter tool 22 (FIG. 2) is enclosed within the housing 26 and performs milling operation on the work surface 12.

The side plate 32 is installed on the first side 36 of the housing 26. The side plate 32 includes a first cutout section 44. The first cutout section 44 defines a clearance space 45 that allows the driver shaft 24 to extend outwards of the housing 26, to support the rotary cutter tool 22 (FIG. 2) on the main frame 14. More specifically, the neck portion 40 of the driver shaft 24 extends outward of the housing 26, through the clearance space 45, to support the rotary cutter tool 22 (FIG. 2) on the main frame 14.

Furthermore, each of the frontal door 28, the rear door 30, and the side plates 32 extend and retract, relative to the rotary cutter tool 22 (FIG. 2), to correspondingly increase and decrease a depth of cut of the rotary cutter tool 22 (FIG. 2). In general, the side plate 32 moves between a retracted state and an extended state, relative to the rotary cutter tool 22, to correspondingly increase and decrease a depth of cut of the rotary cutter tool 22 (FIG. 2). In the retracted state, as shown in FIG. 2, the neck portion 40 of the driver shaft 24 abuts with the first cutout section 44 of the side plate 32. In such situation, negligible gap is observed between the driver shaft 24 and the side plate 32 and therefore the side plate 32 individually prevents unwanted material discharge from the housing 26. In the extended state of the side plate 32, as shown in FIG. 3, the first cutout section 44 of the side plate 32 is at a distance from the neck portion 40 of the driver shaft 24. Therefore, a gap (not shown) is formed between the neck portion 40 of the driver shaft 24 and the first cutout section 44 of the side plate 32, in the extended state of the side plate 32. In such situations, the sealing assembly 34 is required to cover the gap (not shown) between the neck portion 40 and the first cutout section 44.

Referring to FIGS. 4 and 5, the sealing assembly 34 is installed proximal to the first cutout section 44 of the side plate 32. The sealing assembly 34 includes a pair of lateral retention plates 46, a base retention plate 48, and a guard member 50. In the current embodiment, the sealing assembly 34 includes an additional secondary guard member 52, that works in conjunction with the guard member 50, to cover the gap (not shown), in extreme extended state of the side plate 32. Although, the present disclosure contemplates usage of both the guard member 50 and the secondary guard member 52, usage of only the guard member 50, to cover the gap (not shown), may also be contemplated.

The lateral retention plates 46 are installed on each side of the first cutout section 44 of the side plate 32. Each of the lateral retention plates 46 define lateral retention portions 54. The lateral retention portions 54 attaches with the side plate 32, to install the lateral retention plates 46 on the side plate 32. An attachment means between the lateral retention portions 54 and the side plate 32 may include, such as hut not limited to, a bolt attachment means, a rivet attachment means, or a weld attachment means.

The base retention plate 48 (FIG. 4) is installed on the side plate 32, below the first cutout section 44 of the side plate 32. The base retention plate 48 defines a base retention portion 56 (FIG. 4). The base retention portion 56 (FIG. 4) attaches with the side plate 32, to install the base retention plate 48 (FIG. 4) on the side plate 32. An attachment means between the base retention portion 56 (FIG. 4) and the side plate 32 may include, such as but not limited to, a bolt attachment means, a rivet attachment means, or a weld attachment means.

The guard member 50 is outer guard of the sealing assembly 34. The guard member 50 is slideably disposed within the lateral retention plates 46 and the base retention plate 48 (FIG. 4). The guard member 50 is capable of sliding, relative to the side plate 32, in a vertical direction, A. The guard member 50 includes a second cutout section 57. The second cutout section 57 complies with the first cutout section 44 and allows the neck portion 40 of the driver shaft 24, to extend outwards of the sealing assembly 34. The second cutout section 57 is engageable with the neck portion 40 of the driver shaft 24. In the retracted state of the side plate 32, the guard member 50 is positioned adjacent and proximal to the lower portion 42 of the side plate 32. In the extended position of the side plate 32, the second cutout section 57 of the guard member 50 engages with the neck portion 40 of the driver shaft 24, to restrict a movement of the guard member 50. This causes the guard member 50 to slide relative to the side plate 32 and position the second cutout section 57 distal from the lower portion 42 of the side plate 32. More specifically, the guard member 50 hangs in front of and covers the gap (not shown), in the extended state of the side plate 32. Additionally, the guard member 50 includes a pair of follow-up pins 58 (FIG. 5), which engages and deploy the secondary guard member 52, in high extreme extended state of the side plate 32.

In the current embodiment, the secondary guard member 52 is an inner guard of the sealing assembly 34. Similar to the guard member 50, the secondary guard member 52 is slideably disposed within the lateral retention plates 46 and the base retention plate 48 (FIG. 4). The secondary guard member 52 is sandwiched between the guard member 50 and the side plate 32. The secondary guard member 52 includes a pair of extruded portions 60, which are engageable with the follow-up pins 58 (FIG. 5) of the guard member 50. Therefore, the secondary guard member 52 is slideably trailable with the guard member 50. More specifically, in the extreme extended state of the side plate 32, the follow-up pins 58 engages with the extended portions 60 of the secondary guard member 52, to restrict the movement of the secondary guard member 52 and deploy in front of the gap (not shown). Therefore, in the extreme extended state of the side plate 32, each of the guard member 50 and the secondary guard member 52 covers the gap (not shown), between the side plate 32 and the driver shaft 24.

INDUSTRIAL APPLICABILITY

In operation, the rotary cutter tool 22 is disposed within the housing 26 of the rotary cutter assembly 20 and performs milling operation on the work surface 12. More specifically, the rotary cutter tool 22 cuts and removes a portion of the work surface 12, to perform the milling operation. The side plate 32, in conjunction with the sealing assembly 34, prevents unwanted discharge of the milled material, through the first side 30 of the housing 26. The side plate 32 is adapted to switch between the retracted state and the extended state, to increase and/or decrease the depth of cut of the rotary cutter tool 22 on the work surface 12.

In the retracted state of the side plate 32, as is shown in FIG. 2, the neck portion 40 of the driver shaft 24 abuts with the first cutout section 44 of the side plate 32 and no gap is formed between the side plate 32 and the driver shaft 24. Therefore, the side plate 32 individually prevents material discharge through the first side 30. The sealing assembly 34 is not required, for the purpose. In such situations, the guard member 50 and the secondary guard member 52 are positioned adjacent to the side plate 32, proximal to the lower portion 42 of the housing 26. In certain situations, such as to decrease a depth of cut of the rotary cutter tool 22, the side plate 32 is manipulated, to operate in the extended state.

In the extended state of the side plate 32, as is shown in FIG. 3, the first cutout section 44 of the side plate 32 is at a distance from the neck portion 40 of the driver shaft 24 and a gap (not shown) is formed between the first cutout section 44 and the neck portion 40. Therefore, the side plate 32 and the sealing assembly 34, in conjunction, prevent discharge of the milled material through the first side 30. More specifically, the sealing assembly 34 prevents discharge of the milled material through the gap (not shown), in the extended state of the side plate 32. In such situations, the neck portion 40 of the driver shaft 24 engages with the guard member 50, to restrict a movement of the guard member 50. As the movement of the guard member 50 is restricted, it slides relative to the side plate 32, to hang in front of the gap (not shown). Therefore, the guard member 50 prevents material discharge, through the gap (not shown), in the extended state of the side plate 32. This avoids need of flexible mats around the gap (not shown), between the first cutout section 44 and the neck portion 40.

Furthermore, in extreme extended state of the side plate 32, the gap (not shown) enlarges and the guard member 50 is not enough to cover the gap (not shown). In such situations, the follow-up pins 58 of the guard member 50 engages with the extruded portions 60 of the secondary guard member 52, to restrict the movement of the secondary guard member 52 as well. This facilitates the secondary guard member 52 to be deployed in front of the gap (not shown), in conjunction with the guard member 50. Therefore, in the extreme extended state of the side plate 32, each of the guard member 50 and the secondary guard member 52 covers the gap (not shown), between the side plate 32 and the driver shaft 24.

The many features and advantages of the disclosure are apparent from the detailed specification, and thus, it is intended by the appended claims to cover all such features and advantages of the disclosure that fall within the true spirit and scope thereof. Further, since numerous modifications and variations will readily occur to those skilled in the art. It is not desired to limit the disclosure to the exact construction and operation illustrated and described, and, accordingly, all suitable modifications and equivalents may be resorted to that fall within the scope of the disclosure. 

What is claimed is:
 1. A road-milling machine, comprising: a rotary cutter assembly, including: a rotary cutter tool having a drive axis; a driver shaft coaxially attached to the rotary cutter tool along the drive axis, the driver shaft being adapted to rotate the rotary cutter tool, the driver shaft including a neck portion; a housing defining a first side and a second side, the housing being adapted to enclose the rotary cutter tool and at least a portion of the driver shaft: a side plate installed on the first side of the housing, the side plate having a first cutout section, the first cutout section defining a clearance space that allows the neck portion of the driver shaft to extend outward of the side plate, wherein the side plate is movable between an extended state and a retracted state relative to the neck portion of the driver shaft; and a sealing assembly installed proximal to the first cutout section of the side plate, the sealing assembly including: a guard member slideably arranged relative to the side plate, the guard member including a second cutout section, the second cutout section allows the driver shaft to extend outward of the sealing assembly, wherein in the retracted state of the side plate, the guard member is positioned adjacent to the side plate and proximal to a lower portion of the side plate, wherein in the extended state of the side plate, the second cutout section of the guard member engages with the neck portion and limits a movement of the guard member, to position the guard member distal to the lower portion of the side plate. 